<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="generator" content="Asciidoctor 2.0.23">
<meta name="description" content="Learn how to install the USBX device stack, as well as the important host considerations you need to think about before you install.">
<title>Chapter 2 - USBX Device Stack Installation</title>
<link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans:300,300italic,400,400italic,600,600italic%7CNoto+Serif:400,400italic,700,700italic%7CDroid+Sans+Mono:400,700">
<style>
/*! Asciidoctor default stylesheet | MIT License | https://asciidoctor.org */
/* Uncomment the following line when using as a custom stylesheet */
/* @import "https://fonts.googleapis.com/css?family=Open+Sans:300,300italic,400,400italic,600,600italic%7CNoto+Serif:400,400italic,700,700italic%7CDroid+Sans+Mono:400,700"; */
html{font-family:sans-serif;-webkit-text-size-adjust:100%}
a{background:none}
a:focus{outline:thin dotted}
a:active,a:hover{outline:0}
h1{font-size:2em;margin:.67em 0}
b,strong{font-weight:bold}
abbr{font-size:.9em}
abbr[title]{cursor:help;border-bottom:1px dotted #dddddf;text-decoration:none}
dfn{font-style:italic}
hr{height:0}
mark{background:#ff0;color:#000}
code,kbd,pre,samp{font-family:monospace;font-size:1em}
pre{white-space:pre-wrap}
q{quotes:"\201C" "\201D" "\2018" "\2019"}
small{font-size:80%}
sub,sup{font-size:75%;line-height:0;position:relative;vertical-align:baseline}
sup{top:-.5em}
sub{bottom:-.25em}
img{border:0}
svg:not(:root){overflow:hidden}
figure{margin:0}
audio,video{display:inline-block}
audio:not([controls]){display:none;height:0}
fieldset{border:1px solid silver;margin:0 2px;padding:.35em .625em .75em}
legend{border:0;padding:0}
button,input,select,textarea{font-family:inherit;font-size:100%;margin:0}
button,input{line-height:normal}
button,select{text-transform:none}
button,html input[type=button],input[type=reset],input[type=submit]{-webkit-appearance:button;cursor:pointer}
button[disabled],html input[disabled]{cursor:default}
input[type=checkbox],input[type=radio]{padding:0}
button::-moz-focus-inner,input::-moz-focus-inner{border:0;padding:0}
textarea{overflow:auto;vertical-align:top}
table{border-collapse:collapse;border-spacing:0}
*,::before,::after{box-sizing:border-box}
html,body{font-size:100%}
body{background:#fff;color:rgba(0,0,0,.8);padding:0;margin:0;font-family:"Noto Serif","DejaVu Serif",serif;line-height:1;position:relative;cursor:auto;-moz-tab-size:4;-o-tab-size:4;tab-size:4;word-wrap:anywhere;-moz-osx-font-smoothing:grayscale;-webkit-font-smoothing:antialiased}
a:hover{cursor:pointer}
img,object,embed{max-width:100%;height:auto}
object,embed{height:100%}
img{-ms-interpolation-mode:bicubic}
.left{float:left!important}
.right{float:right!important}
.text-left{text-align:left!important}
.text-right{text-align:right!important}
.text-center{text-align:center!important}
.text-justify{text-align:justify!important}
.hide{display:none}
img,object,svg{display:inline-block;vertical-align:middle}
textarea{height:auto;min-height:50px}
select{width:100%}
.subheader,.admonitionblock td.content>.title,.audioblock>.title,.exampleblock>.title,.imageblock>.title,.listingblock>.title,.literalblock>.title,.stemblock>.title,.openblock>.title,.paragraph>.title,.quoteblock>.title,table.tableblock>.title,.verseblock>.title,.videoblock>.title,.dlist>.title,.olist>.title,.ulist>.title,.qlist>.title,.hdlist>.title{line-height:1.45;color:#7a2518;font-weight:400;margin-top:0;margin-bottom:.25em}
div,dl,dt,dd,ul,ol,li,h1,h2,h3,#toctitle,.sidebarblock>.content>.title,h4,h5,h6,pre,form,p,blockquote,th,td{margin:0;padding:0}
a{color:#2156a5;text-decoration:underline;line-height:inherit}
a:hover,a:focus{color:#1d4b8f}
a img{border:0}
p{line-height:1.6;margin-bottom:1.25em;text-rendering:optimizeLegibility}
p aside{font-size:.875em;line-height:1.35;font-style:italic}
h1,h2,h3,#toctitle,.sidebarblock>.content>.title,h4,h5,h6{font-family:"Open Sans","DejaVu Sans",sans-serif;font-weight:300;font-style:normal;color:#ba3925;text-rendering:optimizeLegibility;margin-top:1em;margin-bottom:.5em;line-height:1.0125em}
h1 small,h2 small,h3 small,#toctitle small,.sidebarblock>.content>.title small,h4 small,h5 small,h6 small{font-size:60%;color:#e99b8f;line-height:0}
h1{font-size:2.125em}
h2{font-size:1.6875em}
h3,#toctitle,.sidebarblock>.content>.title{font-size:1.375em}
h4,h5{font-size:1.125em}
h6{font-size:1em}
hr{border:solid #dddddf;border-width:1px 0 0;clear:both;margin:1.25em 0 1.1875em}
em,i{font-style:italic;line-height:inherit}
strong,b{font-weight:bold;line-height:inherit}
small{font-size:60%;line-height:inherit}
code{font-family:"Droid Sans Mono","DejaVu Sans Mono",monospace;font-weight:400;color:rgba(0,0,0,.9)}
ul,ol,dl{line-height:1.6;margin-bottom:1.25em;list-style-position:outside;font-family:inherit}
ul,ol{margin-left:1.5em}
ul li ul,ul li ol{margin-left:1.25em;margin-bottom:0}
ul.circle{list-style-type:circle}
ul.disc{list-style-type:disc}
ul.square{list-style-type:square}
ul.circle ul:not([class]),ul.disc ul:not([class]),ul.square ul:not([class]){list-style:inherit}
ol li ul,ol li ol{margin-left:1.25em;margin-bottom:0}
dl dt{margin-bottom:.3125em;font-weight:bold}
dl dd{margin-bottom:1.25em}
blockquote{margin:0 0 1.25em;padding:.5625em 1.25em 0 1.1875em;border-left:1px solid #ddd}
blockquote,blockquote p{line-height:1.6;color:rgba(0,0,0,.85)}
@media screen and (min-width:768px){h1,h2,h3,#toctitle,.sidebarblock>.content>.title,h4,h5,h6{line-height:1.2}
h1{font-size:2.75em}
h2{font-size:2.3125em}
h3,#toctitle,.sidebarblock>.content>.title{font-size:1.6875em}
h4{font-size:1.4375em}}
table{background:#fff;margin-bottom:1.25em;border:1px solid #dedede;word-wrap:normal}
table thead,table tfoot{background:#f7f8f7}
table thead tr th,table thead tr td,table tfoot tr th,table tfoot tr td{padding:.5em .625em .625em;font-size:inherit;color:rgba(0,0,0,.8);text-align:left}
table tr th,table tr td{padding:.5625em .625em;font-size:inherit;color:rgba(0,0,0,.8)}
table tr.even,table tr.alt{background:#f8f8f7}
table thead tr th,table tfoot tr th,table tbody tr td,table tr td,table tfoot tr td{line-height:1.6}
h1,h2,h3,#toctitle,.sidebarblock>.content>.title,h4,h5,h6{line-height:1.2;word-spacing:-.05em}
h1 strong,h2 strong,h3 strong,#toctitle strong,.sidebarblock>.content>.title strong,h4 strong,h5 strong,h6 strong{font-weight:400}
.center{margin-left:auto;margin-right:auto}
.stretch{width:100%}
.clearfix::before,.clearfix::after,.float-group::before,.float-group::after{content:" ";display:table}
.clearfix::after,.float-group::after{clear:both}
:not(pre).nobreak{word-wrap:normal}
:not(pre).nowrap{white-space:nowrap}
:not(pre).pre-wrap{white-space:pre-wrap}
:not(pre):not([class^=L])>code{font-size:.9375em;font-style:normal!important;letter-spacing:0;padding:.1em .5ex;word-spacing:-.15em;background:#f7f7f8;border-radius:4px;line-height:1.45;text-rendering:optimizeSpeed}
pre{color:rgba(0,0,0,.9);font-family:"Droid Sans Mono","DejaVu Sans Mono",monospace;line-height:1.45;text-rendering:optimizeSpeed}
pre code,pre pre{color:inherit;font-size:inherit;line-height:inherit}
pre>code{display:block}
pre.nowrap,pre.nowrap pre{white-space:pre;word-wrap:normal}
em em{font-style:normal}
strong strong{font-weight:400}
.keyseq{color:rgba(51,51,51,.8)}
kbd{font-family:"Droid Sans Mono","DejaVu Sans Mono",monospace;display:inline-block;color:rgba(0,0,0,.8);font-size:.65em;line-height:1.45;background:#f7f7f7;border:1px solid #ccc;border-radius:3px;box-shadow:0 1px 0 rgba(0,0,0,.2),inset 0 0 0 .1em #fff;margin:0 .15em;padding:.2em .5em;vertical-align:middle;position:relative;top:-.1em;white-space:nowrap}
.keyseq kbd:first-child{margin-left:0}
.keyseq kbd:last-child{margin-right:0}
.menuseq,.menuref{color:#000}
.menuseq b:not(.caret),.menuref{font-weight:inherit}
.menuseq{word-spacing:-.02em}
.menuseq b.caret{font-size:1.25em;line-height:.8}
.menuseq i.caret{font-weight:bold;text-align:center;width:.45em}
b.button::before,b.button::after{position:relative;top:-1px;font-weight:400}
b.button::before{content:"[";padding:0 3px 0 2px}
b.button::after{content:"]";padding:0 2px 0 3px}
p a>code:hover{color:rgba(0,0,0,.9)}
#header,#content,#footnotes,#footer{width:100%;margin:0 auto;max-width:62.5em;*zoom:1;position:relative;padding-left:.9375em;padding-right:.9375em}
#header::before,#header::after,#content::before,#content::after,#footnotes::before,#footnotes::after,#footer::before,#footer::after{content:" ";display:table}
#header::after,#content::after,#footnotes::after,#footer::after{clear:both}
#content{margin-top:1.25em}
#content::before{content:none}
#header>h1:first-child{color:rgba(0,0,0,.85);margin-top:2.25rem;margin-bottom:0}
#header>h1:first-child+#toc{margin-top:8px;border-top:1px solid #dddddf}
#header>h1:only-child{border-bottom:1px solid #dddddf;padding-bottom:8px}
#header .details{border-bottom:1px solid #dddddf;line-height:1.45;padding-top:.25em;padding-bottom:.25em;padding-left:.25em;color:rgba(0,0,0,.6);display:flex;flex-flow:row wrap}
#header .details span:first-child{margin-left:-.125em}
#header .details span.email a{color:rgba(0,0,0,.85)}
#header .details br{display:none}
#header .details br+span::before{content:"\00a0\2013\00a0"}
#header .details br+span.author::before{content:"\00a0\22c5\00a0";color:rgba(0,0,0,.85)}
#header .details br+span#revremark::before{content:"\00a0|\00a0"}
#header #revnumber{text-transform:capitalize}
#header #revnumber::after{content:"\00a0"}
#content>h1:first-child:not([class]){color:rgba(0,0,0,.85);border-bottom:1px solid #dddddf;padding-bottom:8px;margin-top:0;padding-top:1rem;margin-bottom:1.25rem}
#toc{border-bottom:1px solid #e7e7e9;padding-bottom:.5em}
#toc>ul{margin-left:.125em}
#toc ul.sectlevel0>li>a{font-style:italic}
#toc ul.sectlevel0 ul.sectlevel1{margin:.5em 0}
#toc ul{font-family:"Open Sans","DejaVu Sans",sans-serif;list-style-type:none}
#toc li{line-height:1.3334;margin-top:.3334em}
#toc a{text-decoration:none}
#toc a:active{text-decoration:underline}
#toctitle{color:#7a2518;font-size:1.2em}
@media screen and (min-width:768px){#toctitle{font-size:1.375em}
body.toc2{padding-left:15em;padding-right:0}
body.toc2 #header>h1:nth-last-child(2){border-bottom:1px solid #dddddf;padding-bottom:8px}
#toc.toc2{margin-top:0!important;background:#f8f8f7;position:fixed;width:15em;left:0;top:0;border-right:1px solid #e7e7e9;border-top-width:0!important;border-bottom-width:0!important;z-index:1000;padding:1.25em 1em;height:100%;overflow:auto}
#toc.toc2 #toctitle{margin-top:0;margin-bottom:.8rem;font-size:1.2em}
#toc.toc2>ul{font-size:.9em;margin-bottom:0}
#toc.toc2 ul ul{margin-left:0;padding-left:1em}
#toc.toc2 ul.sectlevel0 ul.sectlevel1{padding-left:0;margin-top:.5em;margin-bottom:.5em}
body.toc2.toc-right{padding-left:0;padding-right:15em}
body.toc2.toc-right #toc.toc2{border-right-width:0;border-left:1px solid #e7e7e9;left:auto;right:0}}
@media screen and (min-width:1280px){body.toc2{padding-left:20em;padding-right:0}
#toc.toc2{width:20em}
#toc.toc2 #toctitle{font-size:1.375em}
#toc.toc2>ul{font-size:.95em}
#toc.toc2 ul ul{padding-left:1.25em}
body.toc2.toc-right{padding-left:0;padding-right:20em}}
#content #toc{border:1px solid #e0e0dc;margin-bottom:1.25em;padding:1.25em;background:#f8f8f7;border-radius:4px}
#content #toc>:first-child{margin-top:0}
#content #toc>:last-child{margin-bottom:0}
#footer{max-width:none;background:rgba(0,0,0,.8);padding:1.25em}
#footer-text{color:hsla(0,0%,100%,.8);line-height:1.44}
#content{margin-bottom:.625em}
.sect1{padding-bottom:.625em}
@media screen and (min-width:768px){#content{margin-bottom:1.25em}
.sect1{padding-bottom:1.25em}}
.sect1:last-child{padding-bottom:0}
.sect1+.sect1{border-top:1px solid #e7e7e9}
#content h1>a.anchor,h2>a.anchor,h3>a.anchor,#toctitle>a.anchor,.sidebarblock>.content>.title>a.anchor,h4>a.anchor,h5>a.anchor,h6>a.anchor{position:absolute;z-index:1001;width:1.5ex;margin-left:-1.5ex;display:block;text-decoration:none!important;visibility:hidden;text-align:center;font-weight:400}
#content h1>a.anchor::before,h2>a.anchor::before,h3>a.anchor::before,#toctitle>a.anchor::before,.sidebarblock>.content>.title>a.anchor::before,h4>a.anchor::before,h5>a.anchor::before,h6>a.anchor::before{content:"\00A7";font-size:.85em;display:block;padding-top:.1em}
#content h1:hover>a.anchor,#content h1>a.anchor:hover,h2:hover>a.anchor,h2>a.anchor:hover,h3:hover>a.anchor,#toctitle:hover>a.anchor,.sidebarblock>.content>.title:hover>a.anchor,h3>a.anchor:hover,#toctitle>a.anchor:hover,.sidebarblock>.content>.title>a.anchor:hover,h4:hover>a.anchor,h4>a.anchor:hover,h5:hover>a.anchor,h5>a.anchor:hover,h6:hover>a.anchor,h6>a.anchor:hover{visibility:visible}
#content h1>a.link,h2>a.link,h3>a.link,#toctitle>a.link,.sidebarblock>.content>.title>a.link,h4>a.link,h5>a.link,h6>a.link{color:#ba3925;text-decoration:none}
#content h1>a.link:hover,h2>a.link:hover,h3>a.link:hover,#toctitle>a.link:hover,.sidebarblock>.content>.title>a.link:hover,h4>a.link:hover,h5>a.link:hover,h6>a.link:hover{color:#a53221}
details,.audioblock,.imageblock,.literalblock,.listingblock,.stemblock,.videoblock{margin-bottom:1.25em}
details{margin-left:1.25rem}
details>summary{cursor:pointer;display:block;position:relative;line-height:1.6;margin-bottom:.625rem;outline:none;-webkit-tap-highlight-color:transparent}
details>summary::-webkit-details-marker{display:none}
details>summary::before{content:"";border:solid transparent;border-left:solid;border-width:.3em 0 .3em .5em;position:absolute;top:.5em;left:-1.25rem;transform:translateX(15%)}
details[open]>summary::before{border:solid transparent;border-top:solid;border-width:.5em .3em 0;transform:translateY(15%)}
details>summary::after{content:"";width:1.25rem;height:1em;position:absolute;top:.3em;left:-1.25rem}
.admonitionblock td.content>.title,.audioblock>.title,.exampleblock>.title,.imageblock>.title,.listingblock>.title,.literalblock>.title,.stemblock>.title,.openblock>.title,.paragraph>.title,.quoteblock>.title,table.tableblock>.title,.verseblock>.title,.videoblock>.title,.dlist>.title,.olist>.title,.ulist>.title,.qlist>.title,.hdlist>.title{text-rendering:optimizeLegibility;text-align:left;font-family:"Noto Serif","DejaVu Serif",serif;font-size:1rem;font-style:italic}
table.tableblock.fit-content>caption.title{white-space:nowrap;width:0}
.paragraph.lead>p,#preamble>.sectionbody>[class=paragraph]:first-of-type p{font-size:1.21875em;line-height:1.6;color:rgba(0,0,0,.85)}
.admonitionblock>table{border-collapse:separate;border:0;background:none;width:100%}
.admonitionblock>table td.icon{text-align:center;width:80px}
.admonitionblock>table td.icon img{max-width:none}
.admonitionblock>table td.icon .title{font-weight:bold;font-family:"Open Sans","DejaVu Sans",sans-serif;text-transform:uppercase}
.admonitionblock>table td.content{padding-left:1.125em;padding-right:1.25em;border-left:1px solid #dddddf;color:rgba(0,0,0,.6);word-wrap:anywhere}
.admonitionblock>table td.content>:last-child>:last-child{margin-bottom:0}
.exampleblock>.content{border:1px solid #e6e6e6;margin-bottom:1.25em;padding:1.25em;background:#fff;border-radius:4px}
.sidebarblock{border:1px solid #dbdbd6;margin-bottom:1.25em;padding:1.25em;background:#f3f3f2;border-radius:4px}
.sidebarblock>.content>.title{color:#7a2518;margin-top:0;text-align:center}
.exampleblock>.content>:first-child,.sidebarblock>.content>:first-child{margin-top:0}
.exampleblock>.content>:last-child,.exampleblock>.content>:last-child>:last-child,.exampleblock>.content .olist>ol>li:last-child>:last-child,.exampleblock>.content .ulist>ul>li:last-child>:last-child,.exampleblock>.content .qlist>ol>li:last-child>:last-child,.sidebarblock>.content>:last-child,.sidebarblock>.content>:last-child>:last-child,.sidebarblock>.content .olist>ol>li:last-child>:last-child,.sidebarblock>.content .ulist>ul>li:last-child>:last-child,.sidebarblock>.content .qlist>ol>li:last-child>:last-child{margin-bottom:0}
.literalblock pre,.listingblock>.content>pre{border-radius:4px;overflow-x:auto;padding:1em;font-size:.8125em}
@media screen and (min-width:768px){.literalblock pre,.listingblock>.content>pre{font-size:.90625em}}
@media screen and (min-width:1280px){.literalblock pre,.listingblock>.content>pre{font-size:1em}}
.literalblock pre,.listingblock>.content>pre:not(.highlight),.listingblock>.content>pre[class=highlight],.listingblock>.content>pre[class^="highlight "]{background:#f7f7f8}
.literalblock.output pre{color:#f7f7f8;background:rgba(0,0,0,.9)}
.listingblock>.content{position:relative}
.listingblock code[data-lang]::before{display:none;content:attr(data-lang);position:absolute;font-size:.75em;top:.425rem;right:.5rem;line-height:1;text-transform:uppercase;color:inherit;opacity:.5}
.listingblock:hover code[data-lang]::before{display:block}
.listingblock.terminal pre .command::before{content:attr(data-prompt);padding-right:.5em;color:inherit;opacity:.5}
.listingblock.terminal pre .command:not([data-prompt])::before{content:"$"}
.listingblock pre.highlightjs{padding:0}
.listingblock pre.highlightjs>code{padding:1em;border-radius:4px}
.listingblock pre.prettyprint{border-width:0}
.prettyprint{background:#f7f7f8}
pre.prettyprint .linenums{line-height:1.45;margin-left:2em}
pre.prettyprint li{background:none;list-style-type:inherit;padding-left:0}
pre.prettyprint li code[data-lang]::before{opacity:1}
pre.prettyprint li:not(:first-child) code[data-lang]::before{display:none}
table.linenotable{border-collapse:separate;border:0;margin-bottom:0;background:none}
table.linenotable td[class]{color:inherit;vertical-align:top;padding:0;line-height:inherit;white-space:normal}
table.linenotable td.code{padding-left:.75em}
table.linenotable td.linenos,pre.pygments .linenos{border-right:1px solid;opacity:.35;padding-right:.5em;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none;user-select:none}
pre.pygments span.linenos{display:inline-block;margin-right:.75em}
.quoteblock{margin:0 1em 1.25em 1.5em;display:table}
.quoteblock:not(.excerpt)>.title{margin-left:-1.5em;margin-bottom:.75em}
.quoteblock blockquote,.quoteblock p{color:rgba(0,0,0,.85);font-size:1.15rem;line-height:1.75;word-spacing:.1em;letter-spacing:0;font-style:italic;text-align:justify}
.quoteblock blockquote{margin:0;padding:0;border:0}
.quoteblock blockquote::before{content:"\201c";float:left;font-size:2.75em;font-weight:bold;line-height:.6em;margin-left:-.6em;color:#7a2518;text-shadow:0 1px 2px rgba(0,0,0,.1)}
.quoteblock blockquote>.paragraph:last-child p{margin-bottom:0}
.quoteblock .attribution{margin-top:.75em;margin-right:.5ex;text-align:right}
.verseblock{margin:0 1em 1.25em}
.verseblock pre{font-family:"Open Sans","DejaVu Sans",sans-serif;font-size:1.15rem;color:rgba(0,0,0,.85);font-weight:300;text-rendering:optimizeLegibility}
.verseblock pre strong{font-weight:400}
.verseblock .attribution{margin-top:1.25rem;margin-left:.5ex}
.quoteblock .attribution,.verseblock .attribution{font-size:.9375em;line-height:1.45;font-style:italic}
.quoteblock .attribution br,.verseblock .attribution br{display:none}
.quoteblock .attribution cite,.verseblock .attribution cite{display:block;letter-spacing:-.025em;color:rgba(0,0,0,.6)}
.quoteblock.abstract blockquote::before,.quoteblock.excerpt blockquote::before,.quoteblock .quoteblock blockquote::before{display:none}
.quoteblock.abstract blockquote,.quoteblock.abstract p,.quoteblock.excerpt blockquote,.quoteblock.excerpt p,.quoteblock .quoteblock blockquote,.quoteblock .quoteblock p{line-height:1.6;word-spacing:0}
.quoteblock.abstract{margin:0 1em 1.25em;display:block}
.quoteblock.abstract>.title{margin:0 0 .375em;font-size:1.15em;text-align:center}
.quoteblock.excerpt>blockquote,.quoteblock .quoteblock{padding:0 0 .25em 1em;border-left:.25em solid #dddddf}
.quoteblock.excerpt,.quoteblock .quoteblock{margin-left:0}
.quoteblock.excerpt blockquote,.quoteblock.excerpt p,.quoteblock .quoteblock blockquote,.quoteblock .quoteblock p{color:inherit;font-size:1.0625rem}
.quoteblock.excerpt .attribution,.quoteblock .quoteblock .attribution{color:inherit;font-size:.85rem;text-align:left;margin-right:0}
p.tableblock:last-child{margin-bottom:0}
td.tableblock>.content{margin-bottom:1.25em;word-wrap:anywhere}
td.tableblock>.content>:last-child{margin-bottom:-1.25em}
table.tableblock,th.tableblock,td.tableblock{border:0 solid #dedede}
table.grid-all>*>tr>*{border-width:1px}
table.grid-cols>*>tr>*{border-width:0 1px}
table.grid-rows>*>tr>*{border-width:1px 0}
table.frame-all{border-width:1px}
table.frame-ends{border-width:1px 0}
table.frame-sides{border-width:0 1px}
table.frame-none>colgroup+*>:first-child>*,table.frame-sides>colgroup+*>:first-child>*{border-top-width:0}
table.frame-none>:last-child>:last-child>*,table.frame-sides>:last-child>:last-child>*{border-bottom-width:0}
table.frame-none>*>tr>:first-child,table.frame-ends>*>tr>:first-child{border-left-width:0}
table.frame-none>*>tr>:last-child,table.frame-ends>*>tr>:last-child{border-right-width:0}
table.stripes-all>*>tr,table.stripes-odd>*>tr:nth-of-type(odd),table.stripes-even>*>tr:nth-of-type(even),table.stripes-hover>*>tr:hover{background:#f8f8f7}
th.halign-left,td.halign-left{text-align:left}
th.halign-right,td.halign-right{text-align:right}
th.halign-center,td.halign-center{text-align:center}
th.valign-top,td.valign-top{vertical-align:top}
th.valign-bottom,td.valign-bottom{vertical-align:bottom}
th.valign-middle,td.valign-middle{vertical-align:middle}
table thead th,table tfoot th{font-weight:bold}
tbody tr th{background:#f7f8f7}
tbody tr th,tbody tr th p,tfoot tr th,tfoot tr th p{color:rgba(0,0,0,.8);font-weight:bold}
p.tableblock>code:only-child{background:none;padding:0}
p.tableblock{font-size:1em}
ol{margin-left:1.75em}
ul li ol{margin-left:1.5em}
dl dd{margin-left:1.125em}
dl dd:last-child,dl dd:last-child>:last-child{margin-bottom:0}
li p,ul dd,ol dd,.olist .olist,.ulist .ulist,.ulist .olist,.olist .ulist{margin-bottom:.625em}
ul.checklist,ul.none,ol.none,ul.no-bullet,ol.no-bullet,ol.unnumbered,ul.unstyled,ol.unstyled{list-style-type:none}
ul.no-bullet,ol.no-bullet,ol.unnumbered{margin-left:.625em}
ul.unstyled,ol.unstyled{margin-left:0}
li>p:empty:only-child::before{content:"";display:inline-block}
ul.checklist>li>p:first-child{margin-left:-1em}
ul.checklist>li>p:first-child>.fa-square-o:first-child,ul.checklist>li>p:first-child>.fa-check-square-o:first-child{width:1.25em;font-size:.8em;position:relative;bottom:.125em}
ul.checklist>li>p:first-child>input[type=checkbox]:first-child{margin-right:.25em}
ul.inline{display:flex;flex-flow:row wrap;list-style:none;margin:0 0 .625em -1.25em}
ul.inline>li{margin-left:1.25em}
.unstyled dl dt{font-weight:400;font-style:normal}
ol.arabic{list-style-type:decimal}
ol.decimal{list-style-type:decimal-leading-zero}
ol.loweralpha{list-style-type:lower-alpha}
ol.upperalpha{list-style-type:upper-alpha}
ol.lowerroman{list-style-type:lower-roman}
ol.upperroman{list-style-type:upper-roman}
ol.lowergreek{list-style-type:lower-greek}
.hdlist>table,.colist>table{border:0;background:none}
.hdlist>table>tbody>tr,.colist>table>tbody>tr{background:none}
td.hdlist1,td.hdlist2{vertical-align:top;padding:0 .625em}
td.hdlist1{font-weight:bold;padding-bottom:1.25em}
td.hdlist2{word-wrap:anywhere}
.literalblock+.colist,.listingblock+.colist{margin-top:-.5em}
.colist td:not([class]):first-child{padding:.4em .75em 0;line-height:1;vertical-align:top}
.colist td:not([class]):first-child img{max-width:none}
.colist td:not([class]):last-child{padding:.25em 0}
.thumb,.th{line-height:0;display:inline-block;border:4px solid #fff;box-shadow:0 0 0 1px #ddd}
.imageblock.left{margin:.25em .625em 1.25em 0}
.imageblock.right{margin:.25em 0 1.25em .625em}
.imageblock>.title{margin-bottom:0}
.imageblock.thumb,.imageblock.th{border-width:6px}
.imageblock.thumb>.title,.imageblock.th>.title{padding:0 .125em}
.image.left,.image.right{margin-top:.25em;margin-bottom:.25em;display:inline-block;line-height:0}
.image.left{margin-right:.625em}
.image.right{margin-left:.625em}
a.image{text-decoration:none;display:inline-block}
a.image object{pointer-events:none}
sup.footnote,sup.footnoteref{font-size:.875em;position:static;vertical-align:super}
sup.footnote a,sup.footnoteref a{text-decoration:none}
sup.footnote a:active,sup.footnoteref a:active,#footnotes .footnote a:first-of-type:active{text-decoration:underline}
#footnotes{padding-top:.75em;padding-bottom:.75em;margin-bottom:.625em}
#footnotes hr{width:20%;min-width:6.25em;margin:-.25em 0 .75em;border-width:1px 0 0}
#footnotes .footnote{padding:0 .375em 0 .225em;line-height:1.3334;font-size:.875em;margin-left:1.2em;margin-bottom:.2em}
#footnotes .footnote a:first-of-type{font-weight:bold;text-decoration:none;margin-left:-1.05em}
#footnotes .footnote:last-of-type{margin-bottom:0}
#content #footnotes{margin-top:-.625em;margin-bottom:0;padding:.75em 0}
div.unbreakable{page-break-inside:avoid}
.big{font-size:larger}
.small{font-size:smaller}
.underline{text-decoration:underline}
.overline{text-decoration:overline}
.line-through{text-decoration:line-through}
.aqua{color:#00bfbf}
.aqua-background{background:#00fafa}
.black{color:#000}
.black-background{background:#000}
.blue{color:#0000bf}
.blue-background{background:#0000fa}
.fuchsia{color:#bf00bf}
.fuchsia-background{background:#fa00fa}
.gray{color:#606060}
.gray-background{background:#7d7d7d}
.green{color:#006000}
.green-background{background:#007d00}
.lime{color:#00bf00}
.lime-background{background:#00fa00}
.maroon{color:#600000}
.maroon-background{background:#7d0000}
.navy{color:#000060}
.navy-background{background:#00007d}
.olive{color:#606000}
.olive-background{background:#7d7d00}
.purple{color:#600060}
.purple-background{background:#7d007d}
.red{color:#bf0000}
.red-background{background:#fa0000}
.silver{color:#909090}
.silver-background{background:#bcbcbc}
.teal{color:#006060}
.teal-background{background:#007d7d}
.white{color:#bfbfbf}
.white-background{background:#fafafa}
.yellow{color:#bfbf00}
.yellow-background{background:#fafa00}
span.icon>.fa{cursor:default}
a span.icon>.fa{cursor:inherit}
.admonitionblock td.icon [class^="fa icon-"]{font-size:2.5em;text-shadow:1px 1px 2px rgba(0,0,0,.5);cursor:default}
.admonitionblock td.icon .icon-note::before{content:"\f05a";color:#19407c}
.admonitionblock td.icon .icon-tip::before{content:"\f0eb";text-shadow:1px 1px 2px rgba(155,155,0,.8);color:#111}
.admonitionblock td.icon .icon-warning::before{content:"\f071";color:#bf6900}
.admonitionblock td.icon .icon-caution::before{content:"\f06d";color:#bf3400}
.admonitionblock td.icon .icon-important::before{content:"\f06a";color:#bf0000}
.conum[data-value]{display:inline-block;color:#fff!important;background:rgba(0,0,0,.8);border-radius:50%;text-align:center;font-size:.75em;width:1.67em;height:1.67em;line-height:1.67em;font-family:"Open Sans","DejaVu Sans",sans-serif;font-style:normal;font-weight:bold}
.conum[data-value] *{color:#fff!important}
.conum[data-value]+b{display:none}
.conum[data-value]::after{content:attr(data-value)}
pre .conum[data-value]{position:relative;top:-.125em}
b.conum *{color:inherit!important}
.conum:not([data-value]):empty{display:none}
dt,th.tableblock,td.content,div.footnote{text-rendering:optimizeLegibility}
h1,h2,p,td.content,span.alt,summary{letter-spacing:-.01em}
p strong,td.content strong,div.footnote strong{letter-spacing:-.005em}
p,blockquote,dt,td.content,td.hdlist1,span.alt,summary{font-size:1.0625rem}
p{margin-bottom:1.25rem}
.sidebarblock p,.sidebarblock dt,.sidebarblock td.content,p.tableblock{font-size:1em}
.exampleblock>.content{background:#fffef7;border-color:#e0e0dc;box-shadow:0 1px 4px #e0e0dc}
.print-only{display:none!important}
@page{margin:1.25cm .75cm}
@media print{*{box-shadow:none!important;text-shadow:none!important}
html{font-size:80%}
a{color:inherit!important;text-decoration:underline!important}
a.bare,a[href^="#"],a[href^="mailto:"]{text-decoration:none!important}
a[href^="http:"]:not(.bare)::after,a[href^="https:"]:not(.bare)::after{content:"(" attr(href) ")";display:inline-block;font-size:.875em;padding-left:.25em}
abbr[title]{border-bottom:1px dotted}
abbr[title]::after{content:" (" attr(title) ")"}
pre,blockquote,tr,img,object,svg{page-break-inside:avoid}
thead{display:table-header-group}
svg{max-width:100%}
p,blockquote,dt,td.content{font-size:1em;orphans:3;widows:3}
h2,h3,#toctitle,.sidebarblock>.content>.title{page-break-after:avoid}
#header,#content,#footnotes,#footer{max-width:none}
#toc,.sidebarblock,.exampleblock>.content{background:none!important}
#toc{border-bottom:1px solid #dddddf!important;padding-bottom:0!important}
body.book #header{text-align:center}
body.book #header>h1:first-child{border:0!important;margin:2.5em 0 1em}
body.book #header .details{border:0!important;display:block;padding:0!important}
body.book #header .details span:first-child{margin-left:0!important}
body.book #header .details br{display:block}
body.book #header .details br+span::before{content:none!important}
body.book #toc{border:0!important;text-align:left!important;padding:0!important;margin:0!important}
body.book #toc,body.book #preamble,body.book h1.sect0,body.book .sect1>h2{page-break-before:always}
.listingblock code[data-lang]::before{display:block}
#footer{padding:0 .9375em}
.hide-on-print{display:none!important}
.print-only{display:block!important}
.hide-for-print{display:none!important}
.show-for-print{display:inherit!important}}
@media amzn-kf8,print{#header>h1:first-child{margin-top:1.25rem}
.sect1{padding:0!important}
.sect1+.sect1{border:0}
#footer{background:none}
#footer-text{color:rgba(0,0,0,.6);font-size:.9em}}
@media amzn-kf8{#header,#content,#footnotes,#footer{padding:0}}
</style>
</head>
<body class="article">
<div id="header">
<h1>Chapter 2 - USBX Device Stack Installation</h1>
</div>
<div id="content">
<div class="sect1">
<h2 id="_host_considerations">Host Considerations</h2>
<div class="sectionbody">
<div class="sect2">
<h3 id="_computer_type">Computer Type</h3>
<div class="paragraph">
<p>Embedded development is usually performed on Windows PC or Unix host computers. After the application is compiled, linked, and located on the host, it is downloaded to the target hardware for execution.</p>
</div>
</div>
<div class="sect2">
<h3 id="_download_interfaces">Download Interfaces</h3>
<div class="paragraph">
<p>Usually the target download is done over an RS-232 serial interface, although parallel interfaces, USB, and Ethernet are becoming more popular. See the development tool documentation for available options.</p>
</div>
</div>
<div class="sect2">
<h3 id="_debugging_tools">Debugging Tools</h3>
<div class="paragraph">
<p>Debugging is done typically over the same link as the program image download. A variety of debuggers exist, ranging from small monitor programs running on the target through Background Debug Monitor (BDM) and In-Circuit Emulator (ICE) tools. The ICE tool provides the most robust debugging of actual target hardware.</p>
</div>
</div>
<div class="sect2">
<h3 id="_required_hard_disk_space">Required Hard Disk Space</h3>
<div class="paragraph">
<p>The source code for USBX is delivered in ASCII format and requires approximately 500 KBytes of space on the host computer&#8217;s hard disk.</p>
</div>
</div>
<div class="sect2">
<h3 id="_target_considerations">Target Considerations</h3>
<div class="paragraph">
<p>USBX requires between 24 KBytes and 64 KBytes of Read Only Memory (ROM) on the target in host mode. The amount of memory required is dependent on the type of controller used and the USB classes linked to USBX. Another 32 KBytes of the target&#8217;s Random Access Memory (RAM) are required for USBX global data structures and memory pool. This memory pool can also be adjusted depending on the expected number of devices on the USB and the type of USB controller. The USBX device side requires roughly 10-12 K of ROM depending on the type of device controller. The RAM memory usage depends on the type of class emulated by the device.</p>
</div>
<div class="paragraph">
<p>USBX also relies on ThreadX semaphores, mutexes, and threads for multiple thread protection, and I/O suspension and periodic processing for monitoring the USB bus topology.</p>
</div>
</div>
<div class="sect2">
<h3 id="_product_distribution">Product Distribution</h3>
<div class="paragraph">
<p>USBX can be obtained from our public source code repository at <a href="https://github.com/eclipse-threadx/usbx/" class="bare">https://github.com/eclipse-threadx/usbx/</a>.</p>
</div>
<div class="paragraph">
<p>The following is a list of several important files in the repository.</p>
</div>
<div class="ulist">
<ul>
<li>
<p><strong><em>ux_api.h</em></strong>: This C header file contains all system equates, data structures, and service prototypes.</p>
</li>
<li>
<p><strong><em>ux_port.h</em></strong>: This C header file contains all development-tool-specific data definitions and structures.</p>
</li>
<li>
<p><strong><em>ux.lib</em></strong>:  This is the binary version of the USBX C library. It is distributed with the standard package.</p>
</li>
<li>
<p><strong><em>demo_usbx.c</em></strong>: The C file containing a simple USBX demo</p>
</li>
</ul>
</div>
<div class="paragraph">
<p>All filenames are in lower-case. This naming convention makes it easier to convert the commands to Unix development platforms.</p>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_usbx_installation">USBX Installation</h2>
<div class="sectionbody">
<div class="paragraph">
<p>USBX is installed by cloning the GitHub repository to your local machine. The following is typical syntax for creating a clone of the USBX repository on your PC:</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlight"><code class="language-c" data-lang="c">    git clone https://github.com/eclipse-threadx/usbx</code></pre>
</div>
</div>
<div class="paragraph">
<p>Alternatively you can download a copy of the repository using the download button on the GitHub main page.</p>
</div>
<div class="paragraph">
<p>You will also find instructions for building the USBX library on the front page of the online repository.</p>
</div>
<div class="paragraph">
<p>The following general instructions apply to virtually any installation:</p>
</div>
<div class="olist arabic">
<ol class="arabic">
<li>
<p>Use the same directory in which you previously installed ThreadX on the host hard drive. All USBX names are unique and will not interfere with the previous USBX installation.</p>
</li>
<li>
<p>Add a call to <strong><em>ux_system_initialize</em></strong> at or near the beginning of <strong><em>tx_application_define</em></strong>. This is where the USBX resources are initialized.</p>
</li>
<li>
<p>Add a call to <strong><em>ux_device_stack_initialize</em>.</strong></p>
</li>
<li>
<p>Add one or more calls to initialize the required USBX classes (either host and/or devices classes)</p>
</li>
<li>
<p>Add one or more calls to initialize the device controller available in the system.</p>
</li>
<li>
<p></p>
<table class="tableblock frame-all grid-all stretch">
<colgroup>
<col style="width: 100%;">
</colgroup>
<tbody>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">It may be required to modify the tx_low_level_initialize.c file to add low-level hardware initialization and interrupt vector routing. This is specific to the hardware platform and will not be discussed here.</p></td>
</tr>
</tbody>
</table>
</li>
<li>
<p>Compile application source code and link with the USBX and ThreadX run time libraries (FileX and/or NetX Duo may also be required if the USB storage class and/or USB network classes are to be compiled in), ux.a (or ux.lib) and tx.a (or tx.lib). The resulting can be downloaded to the target and executed!</p>
</li>
</ol>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_configuration_options">Configuration Options</h2>
<div class="sectionbody">
<div class="paragraph">
<p>There are several configuration options for building the USBX library. All options are located in the <strong><em>ux_user.h</em></strong>.</p>
</div>
<div class="paragraph">
<p>The list below details each configuration option.</p>
</div>
<table class="tableblock frame-all grid-all stretch">
<colgroup>
<col style="width: 50%;">
<col style="width: 50%;">
</colgroup>
<thead>
<tr>
<th class="tableblock halign-left valign-top">Configuration&nbsp;Option</th>
<th class="tableblock halign-left valign-top">Description</th>
</tr>
</thead>
<tbody>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_PERIODIC_RATE</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This value represents how many ticks per seconds for a specific hardware platform. The default is 1000 indicating 1 tick per millisecond.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_THREAD_STACK_SIZE</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This value is the size of the stack in bytes for the USBX threads. It can be typically 1024 bytes or 2048 bytes depending on the processor used and the host controller.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_THREAD_PRIORITY_ENUM</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This is the ThreadX priority value for the USBX enumeration threads that monitors the bus topology.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_THREAD_PRIORITY_CLASS</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This is the ThreadX priority value for the standard USBX threads.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_THREAD_PRIORITY_KEYBOARD</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This is the ThreadX priority value for the USBX HID keyboard class.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_THREAD_PRIORITY_DCD</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This is the ThreadX priority value for the device controller thread.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_NO_TIME_SLICE</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This value actually defines the time slice that will be used for threads. For example, if defined to 0, the ThreadX target port does not use time slices.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_MAX_SLAVE_CLASS_DRIVER</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This is the maximum number of USBX classes that can be registered via ux_device_stack_class_register.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_MAX_SLAVE_LUN</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This value represents the current number of SCSI logical units represented in the device storage class driver.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_SLAVE_CLASS_STORAGE_INCLUDE_MMC</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">If defined, the storage class will handle Multi-Media Commands (MMC) that is, DVD-ROM.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_DEVICE_CLASS_CDC_ECM_NX_PKPOOL_ENTRIES</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This value represents the number of NetX packets in the CDC-ECM class' packet pool. The default is 16.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_SLAVE_REQUEST_CONTROL_MAX_LENGTH</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This value represents the maximum number of bytes received on a control endpoint in the device stack. The default is 256 bytes but can be reduced in memory constraint environments.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_DEVICE_CLASS_HID_EVENT_BUFFER_LENGTH</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This value represents the maximum length in bytes of a HID report.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_DEVICE_CLASS_HID_MAX_EVENTS_QUEUE</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This value represents the maximum number of HID reports that can be queued at once.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_SLAVE_REQUEST_DATA_MAX_LENGTH</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">This value represents the maximum number of bytes received on a bulk endpoint in the device stack. The default is 4096 bytes but can be reduced in memory constraint environments.</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock"><strong>UX_DEVICE_BIDIRECTIONAL_ENDPOINT_SUPPORT</strong></p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">If defined, the device side enables bi-directional-endpoints support, e.g., endpoints addressed 0x01 and 0x81. Otherwise (the default case), endpoint number must be unique in same configuration. Note the feature must be used with compatible DCD and peripheral.</p></td>
</tr>
</tbody>
</table>
</div>
</div>
<div class="sect1">
<h2 id="_source_code_tree">Source Code Tree</h2>
<div class="sectionbody">
<div class="paragraph">
<p>The USBX files are provided in several directories.</p>
</div>
<div class="imageblock">
<div class="content">
<img src="usbx-device-stack/source-code-tree.png" alt="Source Code Tree">
</div>
</div>
<div class="paragraph">
<p>In order to make the files recognizable by their names, the following convention has been adopted:</p>
</div>
<table class="tableblock frame-all grid-all stretch">
<colgroup>
<col style="width: 50%;">
<col style="width: 50%;">
</colgroup>
<thead>
<tr>
<th class="tableblock halign-left valign-top">File Suffix Name</th>
<th class="tableblock halign-left valign-top">File description</th>
</tr>
</thead>
<tbody>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ux_host_stack</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">usbx host stack core files</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ux_host_class</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">usbx host stack classes files</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ux_hcd</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">usbx host stack controller driver files</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ux_device_stack</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">usbx device stack core files</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ux_device_class</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">usbx device stack classes files</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ux_dcd</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">usbx device stack controller driver files</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ux_otg</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">usbx otg controller driver related files</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ux_pictbridge</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">usbx pictbridge files</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ux_utility</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">usbx utility functions</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">demo_usbx</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">demonstration files for USBX</p></td>
</tr>
</tbody>
</table>
</div>
</div>
<div class="sect1">
<h2 id="_initialization_of_usbx_resources">Initialization of USBX resources</h2>
<div class="sectionbody">
<div class="paragraph">
<p>USBX has its own memory manager. The memory needs to be allocated to USBX before the host or device side of USBX is initialized. USBX memory manager can accommodate systems where memory can be cached.</p>
</div>
<div class="paragraph">
<p>The following function initializes USBX memory resources with 128 K of regular memory and no separate pool for cache safe memory:</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlight"><code class="language-c" data-lang="c">/* Initialize USBX Memory */
ux_system_initialize(memory_pointer,(128*1024),UX_NULL,0);</code></pre>
</div>
</div>
<div class="paragraph">
<p>The prototype for the ux_system_initialize is as follows:</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlight"><code class="language-c" data-lang="c">UINT ux_system_initialize(VOID *regular_memory_pool_start,
        ULONG regular_memory_size,
        VOID *cache_safe_memory_pool_start,
        ULONG cache_safe_memory_size);</code></pre>
</div>
</div>
<div class="paragraph">
<p>Input parameters:</p>
</div>
<table class="tableblock frame-all grid-all stretch">
<colgroup>
<col style="width: 50%;">
<col style="width: 50%;">
</colgroup>
<thead>
<tr>
<th class="tableblock halign-left valign-top">Parameter</th>
<th class="tableblock halign-left valign-top">Description</th>
</tr>
</thead>
<tbody>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">VOID *regular_memory_pool_start</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Beginning of the regular memory pool</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ULONG regular_memory_size</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Size of the regular memory pool</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">VOID *cache_safe_memory_pool_start</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Beginning of the cache safe memory pool</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ULONG cache_safe_memory_size</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Size of the cache safe memory pool</p></td>
</tr>
</tbody>
</table>
<div class="paragraph">
<p>Not all systems require the definition of cache safe memory. In such a system, the values passed during the initialization for the memory pointer will be set to UX_NULL and the size of the pool to 0. USBX will then use the regular memory pool in lieu of the cache safe pool.</p>
</div>
<div class="paragraph">
<p>In a system where the regular memory is not cache safe and a controller requires to perform DMA memory it is necessary to define a memory pool in a cache safe zone.</p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_uninitialization_of_usbx_resources">Uninitialization of USBX resources</h2>
<div class="sectionbody">
<div class="paragraph">
<p>USBX can be terminated by releasing its resources. Prior to terminating usbx, all classes and controller resources need to be terminated properly. The following function uninitializes USBX memory resources:</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlight"><code class="language-c" data-lang="c">/* Unitialize USBX Resources */

ux_system_uninitialize();</code></pre>
</div>
</div>
<div class="paragraph">
<p>The prototype for the ux_system_initialize is as follows:</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlight"><code class="language-c" data-lang="c">UINT ux_system_uninitialize(VOID);</code></pre>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_definition_of_usb_device_controller">Definition of USB Device Controller</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Only one USB device controller can be defined at any time to operate in device mode. The application initialization file should contain this definition. The following line performs the definition of a generic usb controller:</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlight"><code class="language-c" data-lang="c">ux_dcd_controller_initialize(0x7BB00000, 0, 0xB7A00000);</code></pre>
</div>
</div>
<div class="paragraph">
<p>The USB device initialization has the following prototype:</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlight"><code class="language-c" data-lang="c">UINT ux_dcd_controller_initialize(ULONG dcd_io,
    ULONG dcd_irq, ULONG dcd_vbus_address);</code></pre>
</div>
</div>
<div class="paragraph">
<p>with the following parameters:</p>
</div>
<table class="tableblock frame-all grid-all stretch">
<colgroup>
<col style="width: 50%;">
<col style="width: 50%;">
</colgroup>
<thead>
<tr>
<th class="tableblock halign-left valign-top">Parameter</th>
<th class="tableblock halign-left valign-top">Description</th>
</tr>
</thead>
<tbody>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ULONG dcd_io</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Address of the controller IO</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ULONG dcd_irq</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Interrupt used by the controller</p></td>
</tr>
<tr>
<td class="tableblock halign-left valign-top"><p class="tableblock">ULONG dcd_vbus_address</p></td>
<td class="tableblock halign-left valign-top"><p class="tableblock">Address of the VBUS GPIO</p></td>
</tr>
</tbody>
</table>
<div class="paragraph">
<p>The following example is the initialization of USBX in device mode with the storage device class and a generic controller:</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlight"><code class="language-c" data-lang="c">/* Initialize USBX Memory */

ux_system_initialize(memory_pointer,(128*1024), 0, 0);

/* The code below is required for installing the device portion of USBX */
status = ux_device_stack_initialize(&amp;device_framework_high_speed,
    DEVICE_FRAMEWORK_LENGTH_HIGH_SPEED, &amp;device_framework_full_speed,
    DEVICE_FRAMEWORK_LENGTH_FULL_SPEED, &amp;string_framework,
    STRING_FRAMEWORK_LENGTH, &amp;language_id_framework,
    LANGUAGE_ID_FRAMEWORK_LENGTH, UX_NULL);

/* If status equals UX_SUCCESS, installation was successful. */

/* Store the number of LUN in this device storage instance: single LUN. */
storage_parameter.ux_slave_class_storage_parameter_number_lun = 1;

/* Initialize the storage class parameters for reading/writing to the Flash Disk. */
storage_parameter.ux_slave_class_storage_parameter_lun[0].ux_slave_class_storage_media_last_lba = 0x1e6bfe;
storage_parameter.ux_slave_class_storage_parameter_lun[0].ux_slave_class_storage_media_block_length = 512;
storage_parameter.ux_slave_class_storage_parameter_lun[0].ux_slave_class_storage_media_type = 0;
storage_parameter.ux_slave_class_storage_parameter_lun[0].ux_slave_class_storage_media_removable_flag = 0x80;
storage_parameter.ux_slave_class_storage_parameter_lun[0].ux_slave_class_storage_media_read = tx_demo_thread_flash_media_read;
storage_parameter.ux_slave_class_storage_parameter_lun[0].ux_slave_class_storage_media_write = tx_demo_thread_flash_media_write;
storage_parameter.ux_slave_class_storage_parameter_lun[0].ux_slave_class_storage_media_status = tx_demo_thread_flash_media_status;

/* Initialize the device storage class. The class is connected with interface 0 */
status = ux_device_stack_class_register(ux_system_slave_class_storage_name ux_device_class_storage_entry,
    ux_device_class_storage_thread,0, (VOID *)&amp;storage_parameter);

/* Register the device controllers available in this system */
status = ux_dcd_controller_initialize(0x7BB00000, 0, 0xB7A00000);

/* If status equals UX_SUCCESS, registration was successful. */</code></pre>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_troubleshooting">Troubleshooting</h2>
<div class="sectionbody">
<div class="paragraph">
<p>USBX is delivered with a demonstration file and a simulation environment. It is always a good idea to get the demonstration platform running first&#8212;&#8203;either on the target hardware or a specific demonstration platform.</p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_usbx_version_id">USBX Version ID</h2>
<div class="sectionbody">
<div class="paragraph">
<p>The current version of USBX is available both to the user and the application software during run-time. The programmer can obtain the USBX version from examination of the <strong><em>ux_port.h</em></strong> file. In addition, this file also contains a version history of the corresponding port. Application software can obtain the USBX version by examining the global string <strong><em>_ux_version_id</em></strong>, which is defined in <strong><em>ux_port.h</em></strong>.</p>
</div>
</div>
</div>
</div>
<div id="footer">
<div id="footer-text">
Last updated 2025-02-07 08:25:21 UTC
</div>
</div>
</body>
</html>